Valve



l atented Get. 19, 1926.

prairies s'ra'rss rarsnr orrics;

GUSTAVE lv'i. HELL, OF CLEVELAND, OHIO, ASSIGNOB TO THE CLEVELAND ROCK DRILL COMPANY, OF CLEVELAND, OHIO.

VALVE.

Application filed November 9, 1922.

The present invention is directed to improvements in valves for fluid operated rock drills, and particularly to the valve for dis tributing the motive fluid to the hammer or piston chamber.

The primary object of the invention is to provide a valve of this nature constructed in such a manner that the same will be positive and quick in action, thus assuring if; proper reciprocation of the piston hammer in its cylinder.

With these and other objects in View, as will appear as the description proceeds, the invention accordingly consists in the novel features of construction, combination of elements, and arrangement of parts, hereinafter to be fully described and pointed out in the appended claims.

In the accompanying drawing, in which similar characters of reference denote like and corresponding parts throughout several views thereof:

Figure 1 is a sectional diagrammatic view, showing the piston in its forward position, and the valve shifted to a position to effect the reverse movement of the piston.

Figure 2 is sectional diagrammatic view, the piston being in its rear position, the valve being shown in elevation and shifted to per init fluid to enter behind the piston.

Referring to the drawing, 1 designates the cylinder having the usual chamber A in which is located for reciprocation thepiston B.

Associated with the cylinder 1 is a valve casing 2 in which is provided a chamber 3, the interior wall of which is provided with a centrally located annular groove 4 into which opens the motive fluid supply port 5, there being on opposite sides of the groove 4 annular channels 6 and 6, which have com- 1nunicating therewith, respectively, the main fluid distributing passages 7 and 8, which as usual communicate respectively directly with the front and rear ends of the hammer cham her A.

The wall of the chamber is provided further with annular exhaust channels 9, which are open to atmosphere through the ports 10.

The ends of the valve chamber 8 have engaged therein plugs 11, each plug being provided with annular heads 12 and 13, the latter being of less diameter than the former. One of the plugs has a rod 14 formed integral therewith and has its free end suitably Serial No. 599,950.

secured to the other plug, whereby said plugs are held in their respective operative positions.

Surrounding-the heads 12 are chambers 15 which communicate with the atmosphere through the ducts 16, said chambers being in communication with the hammer chamber A, and also in communication with said chamber through crossed kick-off ports 17 and 17, the purpose of which will appear later.

The valve 18 is provided with a stem 19 having formed integrally therewith a central flange 20 and spaced flanged terminals 21, said stem being provided with an axial bore 22 and end chambers 23 and 23 and recesses 24 and 24, which are of greater diameter than said bore.

The rod 14 is slidable in the bore of the stem, and consequently the heads 12 and 13 of the plugs are received in the end chambers 28 and 23 and recesses 24 and 24. and have substantially the same diameter as said chambers and recesses, respectively. The stem 19 is provided upon opposite sides of the flange 20 with comparatively small orifices 25 and 26 which afford communication between the chambers 6 and 6, and port 7 and 8, and the recesses 24 and 24. Itwill be of course understood that the bore 22 is of such diameter as to prevent leakage of motive fluid from one chamber to the other through said bore.

, The operation is as follows: As shown in Fig. 1 of the drawing the piston B has just completed its forward stroke, and motive fluid under pressure, which enters the cylinder through the passages also enters the port 17' and chambers 15 and 23and forces the valve 18 to the right, whereupon the central flange 20 of the valve assumes the position as shown, thus permitting live air to pass therearound and into the passage 7 to the forward end of the piston. The piston is forced rearwardly, and the valve positive ly held owing to the fact that some live air will enter the recess 24 through the associated orifice 25, and acts upon the head 13. Since the passage 8 is open to the exhaust port 10 pressure will be relieved in the recess 24 with which the orifice 26 communicates, thereby offering no resistance to the live air in the recess 24. It will be observed that the recesses 24 and 24 constitute, in

conjunction with the rod 14, pressure and relief chambers. This operation is of course reversed when the piston B moves in its forward direction.

As shown in Fig. 2 of the drawing the piston B has justcompleted its rearward" stroke and is about to start forwardwhereupon the port 1? has been uncovered thereby to permit live air to pass therethrough to the chamber 23 to force the valve tothe left, and simultaneously live air will enter the recess 2a through the orifice 26, thereby holding the valve.

Since each chamber 15 is open to atmosphere through the ducts l6 residue air from the respective chambers will pass therefrom before the reversal of the valve. These ducts are comparatively small in cross sectional area, and consequently fluid under pressure will act to shift the'valve before passing to atmosphere.

I' claim:

1. In combination with a cylinder, having a piston movable therein, a valve casing having spaced heads, saidheads being surrounded by chambers, a rod'connecting the heads, a valve mounted in the casing for controlling the passage of motive fluid to and from the cylinder, and slidable on the rod, said valve having annular flanged terminals movable into and out of the-cha n bers, said valve having end recesses 00- ope *ative with certain of the heads, the recesses providing alternate pressure and relief chan'ibers, means controlled .bythe piston for alternately admitting fluid under pressure to the chambers, and means controlled by the valve for admitting fluid under pressure to the recesses.

2. In combination with a cylinder, a piston movable therein, a valve casing having heads in its ends, said heads being of different diameters, a rod connecting the heads, a valve in the casing including a stem which slidably engages the rod, said'valve having end chambersand recesses, the said recesses providing alternate relief and pressure chambers, heads of greater diameter entering the end chambers, the heads of lesser diameter entering the recesses, main passages leading from the casing to the op posite ends of the cylinder, the valve stem having orifices therein to aifordfluid communication betweenthe mainpassages and recesses, crossed ports alfording fluid communication between the cylinder and; the

end chambers of the valve, means controlled by the piston for admitting fluid under n essure to the end chambers, and controlled by the valve for admitting fluid under pres sure through the orifices to the recesses.

In combination with a cylinder, a piston reciprocable therein, a valve casing having heads in its ends of different diameters,

rod extending from one head of less diameter through the opposite heads, the heads of, greater diameterhaving surrounding chambers, crossed ports aifording fluid communication between the cylinder and surrounding head chambers, main fluid pavsages leading from the casing to the oppo- I- site' ends ofthe cylinder, a valve for controlling the passage of fluid. to and from the cylinder, said valve including a stem for sli'dably engaging the rod, said valve having end chambers and recesses, the latter surrounding the rod, said chambers forming in conjunctionwith the rod alternate pressure and relief chambers, the heads of greater and lesser diameters entering, respectively, the end chambers and recesses, the valve stem having oriflces for admitting fluid under pressure from the main passages to the recesses, and means controlled by the valve for admitting fluid under pressure throughthe orifices, to the recesses, said piston controlling the admittance of fluid under pressure from the crossed ports to the surrounding chambers, said casing having ductstherein to permit fluid to flow from the surrounding chambers to atmosphere.

4. Incombination with acylinder, a pis ton reciprocable therein, a valve casing having heads at each-end, a rod connecting the heads, a valve .slidably supported upon the rod and including a stem in the casing for controlling the passage of, fluidunder pressure to and from the. cylinder, said valve having end chambers and recesses, said stem having orifices therein opening into said rcceisses, said recesses, constituting alternate pressureand reliefchambers in conjunction with the rod, means controlled by the pis ten for admitting fluid under pressure to the end chambers of the valve, and means controlled by the, valve for admitting fluid under pressure to the recesses through the orifices, as and for thepurpose set forth,

In testimony whereof I have hereunto set my hand.

' GUSTAVE M, NELL. 

